There is a great deal of interest in how structures made from composite materials respond to high levels of electrical currents conducted through them, particularly carbon fiber composite (CFC) structures used in aircraft. Specifically, the concern is about sparking which occurs as a result of the electrical current passing through a joint in the composite structure. This concern exists because of the ignition hazard which is present when current-caused sparking occurs in a hazardous ignitable vapor area, such as fuel tanks in airplanes, especially when the structure is held together by fasteners.
In the prior art, it has been known to safeguard potentially hazardous areas against sparking by applying a sealant material having a high dielectric constant to the joints and fasteners which would otherwise be exposed in the area. Such application, however, is expensive, time-consuming, and adds undesirable weight to the structure.